1. Field of the Invention
This invention relates to imaging systems, and more specifically to an improved imaging system that provides extensive signal processing within each pixel unit.
2. Brief Description of the Prior Art
In order to enhance the performance of infrared detector readout circuits, it is desirable to create a signal that has a high signal to noise ratio and a uniform response to input infrared energy. It is now common to use a chopper positioned in front of the detector array to create a detector signal that alternates at the frequency of the chopper. The amplitude of the signal is varied in response to the variable capacitance of the ferroelectric detector element. Since the scene that the detector is monitoring changes at a much lower rate than the chop frequency, the signal to noise ratio can be enhanced by amplifying and filtering the signal with a low pass filter, as described in U.S. Pat. No. 5,144,133.